The present invention relates to further improvements of foldable box or tote box, particularly to a tote box for holding general merchandise and fresh produce. More particularly, the tote box of the present invention is formed of a board of corrugated materials, especially corrugated plastic materials, and has an improved locking system to facilitate quick assembly of the box and to enhance its stability and strength. A box cover is provided with a similar locking system for quick assembly and stability. The tote box of this invention is designed to be used not only outdoor, such as in the farmland under sunshine, raining, or even snowing weather conditions, but also indoor, such as cold storage or refrigerated transportation of goods, especially fresh produce that should be kept in special environment to preserve their quality.
There are many kinds of boxes or cartons known in the art, that are used for holding goods for storage and transportation. These known boxes are made of various materials, such as cardboard, wood, metal, and plastics. However, all of the known boxes have, respectively, various disadvantages, such as moisture immersion, high cost, or too heavy. Particularly, none of the known foldable boxes is suitable for all environmental conditions, such as sunshine or hot environment, wet or humid conditions, cold or frozen conditions, and stacking-up with heavy load. Therefore, there is a need or demand for a durable box which can be used in any kinds of environment in which a box would be used. At the same time, the box must be cost efficient or economical, easily foldable without use of any glue, tape, nails, or tools, easily transportable as a flat piece or pieces, reusable, light weight, moisture resistant, washable, and capable of stacking-up to bear heavy load for a relatively long period of time. The box should also be recyclable.
At present, no single box can meet all of these requirements. Most of one-piece board of foldable boxes are made of cardboard, waxed cardboard, or thin plastics because thick plastic boards cannot be easily folded. Such boxes usually utilize laminate layers or fillers to reinforce the side and end walls or corners of the box for better support, for instance, the box disclosed in U.S. Pat. No. 3,310,219 to Dlugopolski; However, the locking systems used thereon are not strong enough to hold the box panels together when the box is used in severe conditions, such as moisture, heat, heavy load. The novel locking system of the present invention however, can meet the requirements of strong holding and quick assembly of the box even when the box is used under the severe conditions.
The normal locking system for the boxes are tab and slot engagements that are not deadly locked. For example, the inset tabs and the slots are used in U.S. Pat. No. 3,310,219 to Dlugopolski, and U.S. Pat. No. 3,708,103 to Evants. The barbed tabs are used in U.S. Pat. No. 4,463,997 to Densen, and U.S. Pat. No. 3,991,932 to Carmel et al. These locks are designed for cardboard material which is relatively soft and flexible. The locking system of Densen is a combination of the tab-slot engagement and barbed tabs. The barbed tabs must be bend over at the box corner to assure the locking of the additional tab-slot engagement. The assembly of such box is relatively slow and such locking cannot be used on boxes of thicker plastic materials. Due to moisture immersion or merely worn-out, the tab-slot engagement or barbed tabs, even the combination thereof in Densen, will be weakened.
Therefore, it is an object of the present invention to provide an improved foldable tote box that meets all requirements stated above.
It is another object of the present invention to provide a novel locking system for foldable boxes, that facilitates the quick assembly or disassembly of the box, while provides the box with enhanced strength and stability.
It is a further object of the present invention to provide a foldable tote box that may have hollow support beams at desired locations, such as at two sides or all four sides or four corners for enhancing support strength for stacking-up boxes and providing insulation and cushion functions to absorb impacts.
In accordance with the present invention, a foldable tote box comprises a one-pierce die-cut board of corrugated material, said board including a rectangular bottom panel having a predetermined length and width defined by its two side edges and two end edges; a pair of side-wall panels, each having a folding edge integrally connected to the side edge of the bottom panel and being folded along a first scored folding line at the folding edge to form the side-wall of the box, each of said side-wall panels having a cover panel connected to its top edge opposite to the folding edge and two end edges defining a width of the side-wall panel that defines a height of the box; a pair of end wall panels respectively integrally connected to and extended from the end edges of the bottom panel and folded along second scored folding lines thereat; and a pair of filler beam panels connected to the end edges of each end-wall panel, each of said filler beam panels extending from said respective end edge of said end-wall panel and being folded along a third scored folding line at the end-wall panel end edge to form a hollow support beam; wherein a first pair of locking insert tabs is formed in cutting lines at predetermined locations on the side-wall panel and engaged with a first pair of holding tabs, each of which is formed at a predetermined location on the corresponding filler beam panel so as to secure the support beams formed of the filler beam panels against the corresponding side-wall panels when the box is assembled, and wherein each locking insert tab and its corresponding holding tab are oriented in the same direction.
Alternatively, in addition to the first pair of locking inset tabs and holding tabs, a second pair of locking insert tabs is formed at predetermined locations on said end-wall panel and engaged with a second pair of holding tabs, each of which is formed at a predetermined location on the filler beam panel. In such a case, the support beams formed of the filler beam panels are against the corresponding end-wall panels.
Each of the filler beam panels is divided into four or five sections. In one embodiment of five-section filler beam panel, the first pair of holding tabs is provided at the innermost section to the third folding lines, and the corresponding locking insert tabs are on the side-wall panel. In another embodiment of four-section filler beam panel, the second pair of holding tabs is additionally provided at the outermost section away from the third folding lines, and the corresponding second pair of locking insert tabs on the end-wall panels. In a further embodiment of four-section filler beam panel forming a triangle hollow corner support beam, the sections are somewhat equally divided, but the second innermost section is longer. The first pair of locking insert tabs is provided on the end-wall panels rather than the side-wall panels, and the first pair of holding tabs is on the third section from the third folding line.
Further, there are protruding tabs formed along the top edges of the end-wall panes and filler beam panes, while there are a pair or two pairs of openings at predetermined locations on each cover panel. The openings respectively receive the protruding tabs of the end-wall panels and filler beam panels.
The protruding tab may serve as a stacking tab formed at a top edge of each filler beam panel at a predetermined location. The function of stacking tab is disclosed in U.S. Pat. No. 5,913,474 of the same inventor and assignee. In that Patent, there are notch opening or openings at predetermined locations along the scoring lines on the end wall panel so that the tab of the filler beam panel protrudes through the notch opening or openings when the board is folded to form the box. Thus, the stacking tabs of the lower box, either on the end wall or side-wall beams, will engage with the stacking holes of the upper box to lock the upper box in position, i.e., restricting the movement of the upper box in all directions. In addition, the protruding tabs in the embodiments of the present invention also engage with the openings on the cover panels to secure the cover on the box.
The novel locking system includes a locking insert tab or tabs formed at an appropriate location of the end-wall panel or side-wall panel. The holding tab or tabs are formed on one of sections of the filler beam panel. Thus, the locking insert tab may be pressed and inserted through and held by the holding tab on the hollow support beam formed of the filler beam panel. The insert tab is oriented in the same direction as the holding tab when the box is assembled, that is, a corresponding locking insert tab and holding tab are oriented in the same direction as the tabs engage with one another. The insert and holding tabs are generally cut-out in a U-shape at appropriate location on the side or end walls and filler beam panels. The length of the insert tab is a little bit longer than the holding tab on the support beam. Due to the elasticity of the corrugated board or plastic board, the holding tab on the support beam will hold the insert tab against the wall of the support beam once the insert tab is pressed and inserted through the holding tab which is moved away, by pressing, from its original position and tends to return the original position on the support beam.
Further, a cover piece can be provided with the novel locking system. The cover piece includes nine panels of a top panel, two side panels, two end panels, and four corner panels that are integrally connected to either end panels or side panels. The locking insert tabs are provided on the side panels if the corner panels are connected to the end panels or vice versa. The holding tabs of the locking system are formed on the corner panels.
Various embodiments of the present invention can be well understood in the following descriptions in connection with the accompanying drawings.